#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
	int n, i;
	printf("please enter a integer number,n=?");
	scanf("%d", &n);
	for (i = 2; i < n; i++)
		if (n % i == 0)
			break;
	if (i < n)
		printf("%d is not a prime number.\n", n);
	return 0;
}